Abstract

Web Content Accessibility Guidelines (WCAG) 2.1 covers a wide range of recommendations for making Web content more accessible. Following these guidelines will make content more accessible to a wider range of people with disabilities, including blindness and low vision, deafness and hearing loss, limited movement, speech disabilities, photosensitivity, and combinations of these, and some accommodation for learning disabilities and cognitive limitations; but will not address every user need for people with these disabilities. These guidelines address accessibility of web content on desktops, laptops, tablets, and mobile devices. Following these guidelines will also often make Web content more usable to users in general.

WCAG 2.1 success criteria are written as testable statements that are not technology-specific. Guidance about satisfying the success criteria in specific technologies, as well as general information about interpreting the success criteria, is provided in separate documents. See Web Content Accessibility Guidelines (WCAG) Overview for an introduction and links to WCAG technical and educational material.

WCAG 2.1 extends Web Content Accessibility Guidelines 2.0 [WCAG20], which was published as a W3C Recommendation December 2008. Content that conforms to WCAG 2.1 also conforms to WCAG 2.0, and therefore to policies that reference WCAG 2.0.

Until WCAG 2.1 advances to W3C Recommendation, the current and referenceable document is Web Content Accessibility Guidelines 2.0 [WCAG20], published as a W3C Recommendation December 2008.

Status of This Document

This section describes the status of this document at the time of its publication. Other documents may supersede this document. A list of current W3C publications and the latest revision of this technical report can be found in the W3C technical reports index at https://www.w3.org/TR/.

The primary purpose of the Proposed Recommendation is to collect feedback from the Advisory Committee. W3C Advisory Committee Members are invited to send formal review comments to the W3C Team until 22 May 2018. Comments should be made using the Call for Review WBS form. To comment, aside from Advisory Committee comments, file an issue in the W3C WCAG 2.1 GitHub repository. The Working Group requests that public comments be filed as new issues, one issue per discrete comment. It is free to create a GitHub account to file issues. If filing issues in GitHub is not feasible, send email to public-agwg-comments@w3.org (comment archive). Comments are requested by 22 May 2018. In-progress updates to the document may be viewed in the publicly visible editors' draft.

This document was published by the Accessibility Guidelines Working Group as a Proposed Recommendation.
This document is intended to become a W3C Recommendation.
The W3C Membership and other interested parties are invited to review the document and
send comments to
public-comments-wcag20@w3.org
(subscribe,
archives)
through 22 May 2018. Advisory Committee Representatives should consult their
WBS questionnaires.
Note that substantive technical comments were expected during the Candidate Recommendation
review period that ended 30 March 2018.

Publication as a Proposed Recommendation does not imply endorsement by the W3C
Membership. This is a draft document and may be updated, replaced or obsoleted by other
documents at any time. It is inappropriate to cite this document as other than work in
progress.

Introduction

Web Content Accessibility Guidelines (WCAG) 2.1 defines how to make Web content more accessible to people with disabilities. Accessibility involves a wide range of disabilities, including visual, auditory, physical, speech, cognitive, language, learning, and neurological disabilities. Although these guidelines cover a wide range of issues, they are not able to address the needs of people with all types, degrees, and combinations of disability. These guidelines also make Web content more usable by older individuals with changing abilities due to aging and often improve usability for users in general.

WCAG 2.1 is developed through the W3C process in cooperation with individuals and organizations around the world, with a goal of providing a shared standard for Web content accessibility that meets the needs of individuals, organizations, and governments internationally. WCAG 2.1 builds on WCAG 2.0 [WCAG20], which in turn built on WCAG 1.0 [WAI-WEBCONTENT] and is designed to apply broadly to different Web technologies now and in the future, and to be testable with a combination of automated testing and human evaluation. For an introduction to WCAG, see the Web Content Accessibility Guidelines (WCAG) Overview.

Web accessibility depends not only on accessible content but also on accessible Web browsers and other user agents. Authoring tools also have an important role in Web accessibility. For an overview of how these components of Web development and interaction work together, see:

The individuals and organizations that use WCAG vary widely and include Web designers and developers, policy makers, purchasing agents, teachers, and students. In order to meet the varying needs of this audience, several layers of guidance are provided including overall principles, general guidelines, testable success criteria and a rich collection of sufficient techniques, advisory techniques, and documented common failures with examples, resource links and code.

Guidelines - Under the principles are guidelines. The 12 guidelines provide the basic goals that authors should work toward in order to make content more accessible to users with different disabilities. The guidelines are not testable, but provide the framework and overall objectives to help authors understand the success criteria and better implement the techniques.

Success Criteria - For each guideline, testable success criteria are provided to allow WCAG 2.0 to be used where requirements and conformance testing are necessary such as in design specification, purchasing, regulation, and contractual agreements. In order to meet the needs of different groups and different situations, three levels of conformance are defined: A (lowest), AA, and AAA (highest). Additional information on WCAG levels can be found in Understanding Levels of Conformance.

Sufficient and Advisory Techniques - For each of the guidelines and success criteria in the WCAG 2.0 document itself, the working group has also documented a wide variety of techniques. The techniques are informative and fall into two categories: those that are sufficient for meeting the success criteria and those that are advisory. The advisory techniques go beyond what is required by the individual success criteria and allow authors to better address the guidelines. Some advisory techniques address accessibility barriers that are not covered by the testable success criteria. Where common failures are known, these are also documented. See also Sufficient and Advisory Techniques in Understanding WCAG 2.0.

All of these layers of guidance (principles, guidelines, success criteria, and sufficient and advisory techniques) work together to provide guidance on how to make content more accessible. Authors are encouraged to view and apply all layers that they are able to, including the advisory techniques, in order to best address the needs of the widest possible range of users.

Note that even content that conforms at the highest level (AAA) will not be accessible to individuals with all types, degrees, or combinations of disability, particularly in the cognitive language and learning areas. Authors are encouraged to consider the full range of techniques, including the advisory techniques, as well as to seek relevant advice about current best practice to ensure that Web content is accessible, as far as possible, to this community. Metadata may assist users in finding content most suitable for their needs.

The WCAG 2.0 document is designed to meet the needs of those who need a stable, referenceable technical standard. Other documents, called supporting documents, are based on the WCAG 2.0 document and address other important purposes, including the ability to be updated to describe how WCAG would be applied with new technologies. Supporting documents include:

How to Meet WCAG 2.1 - A customizable quick reference to WCAG 2.1 that includes all of the guidelines, success criteria, and techniques for authors to use as they are developing and evaluating Web content. This includes content from WCAG 2.0 and WCAG 2.1 and can be filtered in many ways to help authors focus on relevant content.

Understanding WCAG 2.1 - A guide to understanding and implementing WCAG 2.1. There is a short "Understanding" document for each guideline and success criterion in WCAG 2.1 as well as key topics.

Techniques for WCAG 2.1 - A collection of techniques and common failures, each in a separate document that includes a description, examples, code and tests.

The WCAG Documents - A diagram and description of how the technical documents are related and linked.

See Web Content Accessibility Guidelines (WCAG) Overview for a description of the WCAG 2.0 supporting material, including education resources related to WCAG 2. Additional resources covering topics such as the business case for Web accessibility, planning implementation to improve the accessibility of Web sites, and accessibility policies are listed in WAI Resources.

WCAG 2.1 meets a set of requirements for WCAG 2.1 which, in turn, inherit requirements from WCAG 2.0. Requirements structure the overall framework of guidelines and ensure backwards compatibility. The Working Group also used a less formal set of acceptance criteria for success criteria, to help ensure success criteria are similar in style and quality to those in WCAG 2.0. These requirements constrained what could be included in WCAG 2.1. This constraint was important to preserve its nature as a dot-release of WCAG 2.

WCAG 2.1 was initiated with the goal to improve accessibility guidance for three major groups: users with cognitive or learning disabilities, users with low vision, and users with disabilities on mobile devices. Many ways to meet these needs were proposed and evaluated, and a set of these were refined by the Working Group. Structural requirements inherited from WCAG 2.0, clarity and impact of proposals, and timeline led to the final set of success criteria included in this version. The Working Group considers that WCAG 2.1 incrementally advances web content accessibility guidance for all these areas, but underscores that not all user needs are met by these guidelines.

WCAG 2.1 builds on and is backwards compatible with WCAG 2.0, meaning web pages that conform to WCAG 2.1 also conform to WCAG 2.0. Authors that are required by policy to conform with WCAG 2.0 will be able to update content to WCAG 2.1 without losing conformance with WCAG 2.0. Authors following both sets of guidelines should be aware of the following differences:

WCAG 2.1 extends WCAG 2.0 by adding new success criteria, definitions to support them, guidelines to organize the additions, and a couple additions to the conformance section. This additive approach helps to make it clear that sites which conform to WCAG 2.1 also conform to WCAG 2.0, thereby meeting conformance obligations that are specific to WCAG 2.0. The Accessibility Guidelines Working Group recommends that sites adopt WCAG 2.1 as their new conformance target, even if formal obligations mention WCAG 2.0, to provide improved accessibility and to anticipate future policy changes.

In order to avoid confusion for implementers for whom backwards compatibility to WCAG 2.0 is important, new success criteria in WCAG 2.1 have been appended to the end of the set of success criteria within their guideline. This avoids the need to change the section number of success criteria from WCAG 2.0, which would be caused by inserting new success critera between existing success ccriteria in the guideline, but it means success criteria in each guideline are no longer grouped by conformance level. The order of success criteria within each guideline does not imply information about conformance level; only the conformance level indicator (A / AA / AAA) on the success criterion itself indicates this. The WCAG 2.1 Quick Reference provides ways to view success criteria grouped by conformance level, along with many other filter and sort options.

WCAG 2.1 uses the same conformance model as WCAG 2.0 with a couple additions, which is described in the Conformance section. It is intended that sites that conform to WCAG 2.1 also conform to WCAG 2.0, which means they meet the requirements of any policies that reference WCAG 2.0, while also better meeting the needs of users on the current Web.

In parallel with WCAG 2.1, the Accessibility Guidelines Working Group is developing another major version of accessibility guidelines. The result of this work is expected to be a more substantial restructuring of web accessibility guidance than would be realistic for dot-releases of WCAG 2. The work follows a research-focused, user-centered design methodology to produce the most effective and flexible outcome, including the roles of content authoring, user agent support, and authoring tool support. This is a multi-year effort, so WCAG 2.1 is needed as an interim measure to provide updated web accessibility guidance to reflect changes on the web since the publication of WCAG 2.0. The Working Group might also develop additional interim versions, continuing with WCAG 2.2, on a similar short timeline to provide additional support while the major version is completed.

If non-text content is a control or accepts user input, then it has a name that describes its purpose. (Refer to Success Criterion 4.1.2 for additional requirements for controls and content that accepts user input.)

Time-Based Media

If non-text content is time-based media, then text alternatives at least provide descriptive
identification of the non-text content. (Refer to Guideline 1.2 for additional requirements for media.)

Test

If non-text content is a test or exercise that would be invalid if presented in text, then text alternatives at least provide descriptive identification of the non-text
content.

Sensory

If non-text content is primarily intended to create a specific sensory experience, then text alternatives at least provide descriptive identification of the non-text
content.

If the purpose of non-text content is to confirm that content is being accessed by
a person rather than a computer, then text alternatives that identify and describe
the purpose of the non-text content are provided, and alternative forms of CAPTCHA
using output modes for different types of sensory perception are provided to accommodate
different disabilities.

Decoration, Formatting, Invisible

If non-text content is pure decoration, is used only for visual formatting, or is not presented to users, then it is implemented
in a way that it can be ignored by assistive technology.

Content does not restrict its view and operation to a single display orientation, such as portrait or landscape, unless a specific display orientation is essential.

Note

Examples where a particular display orientation may be essential are a bank check, a piano application, slides for a projector or television, or virtual reality content where binary display orientation is not applicable.

If any audio on a Web page plays automatically for more than 3 seconds, either a mechanism is available to pause or stop the audio, or a mechanism is available to control audio
volume independently from the overall system volume level.

Note

Since any content that does not meet this success criterion can interfere with a user's
ability to use the whole page, all content on the Web page (whether or not it is used
to meet other success criteria) must meet this success criterion. See Conformance Requirement 5: Non-Interference.

Large-scale text and images of large-scale text have a contrast ratio of at least 3:1;

Incidental

Text or images of text that are part of an inactive user interface component, that are pure decoration, that are not visible to anyone, or that are part of a picture that contains significant
other visual content, have no contrast requirement.

Logotypes

Text that is part of a logo or brand name has no contrast requirement.

Large-scale text and images of large-scale text have a contrast ratio of at least 4.5:1;

Incidental

Text or images of text that are part of an inactive user interface component, that are pure decoration, that are not visible to anyone, or that are part of a picture that contains significant
other visual content, have no contrast requirement.

Logotypes

Text that is part of a logo or brand name has no contrast requirement.

For prerecordedaudio-only content that (1) contains primarily speech in the foreground, (2) is not an audio
CAPTCHA or audio logo, and (3) is not vocalization intended to be primarily musical expression
such as singing or rapping, at least one of the following is true:

No Background

The audio does not contain background sounds.

Turn Off

The background sounds can be turned off.

20 dB

The background sounds are at least 20 decibels lower than the foreground speech content,
with the exception of occasional sounds that last for only one or two seconds.

Note

Per the definition of "decibel," background sound that meets this requirement will
be approximately four times quieter than the foreground speech content.

Except for parts of the content which require two-dimensional layout for usage or meaning.

Note

Note: 320 CSS pixels is equivalent to a starting viewport width of 1280 CSS pixels wide at 400% zoom. For web content which are designed to scroll horizontally (e.g. with vertical text), the 256 CSS pixels is equivalent to a starting viewport height of 1024px at 400% zoom.

Note

Examples of content which require two-dimensional layout are images, maps, diagrams,
video, games, presentations, data tables, and interfaces where it is necessary to keep toolbars in view while
manipulating content.

Visual information used to indicate states and boundaries of user interface components, except for inactive components or where the appearance of the component is determined by the user agent and not modified by the author;

Graphical Objects

Parts of graphics required to understand the content, except when a particular presentation of graphics is essential to the information being conveyed.

In content implemented using markup languages that support the following textstyle properties, no loss of content or functionality occurs by setting all of the following and by changing no other style property:

Line height (line spacing) to at least 1.5 times the font size;

Spacing following paragraphs to at least 2 times the font size;

Letter spacing (tracking) to at least 0.12 times the font size;

Word spacing to at least 0.16 times the font size.

Exception: Human languages and scripts that do not make use of one or more of these text style properties in written text can conform using only the properties that exist for that combination of language and script.

Where receiving and then removing pointer hover or keyboard focus triggers additional content to become visible and then hidden, the following are true:

Dismissable

A mechanism is available to dismiss the additional content without moving pointer hover or keyboard focus, unless the additional content communicates an input error or does not obscure or replace other content;

Hoverable

If pointer hover can trigger the additional content, then the pointer can be moved over the additional content without the additional content disappearing;

Persistent

The additional content remains visible until the hover or focus trigger is removed, the user dismisses it, or its information is no longer valid.

Exception: The visual presentation of the additional content is controlled by the user agent and is not modified by the author.

Note

Examples of additional content controlled by the user agent include browser tooltips created through use of the HTML title attribute.

Note

Custom tooltips, sub-menus, and other nonmodal popups that display on hover and focus are examples of additional content covered by this criterion.

All functionality of the content is operable through a keyboard interface without requiring specific timings for individual keystrokes, except where the underlying
function requires input that depends on the path of the user's movement and not just
the endpoints.

Note

This exception relates to the underlying function, not the input technique. For example,
if using handwriting to enter text, the input technique (handwriting) requires path-dependent
input but the underlying function (text input) does not.

Note

This does not forbid and should not discourage providing mouse input or other input
methods in addition to keyboard operation.

If keyboard focus can be moved to a component of the page using a keyboard interface, then focus can be moved away from that component using only a keyboard interface,
and, if it requires more than unmodified arrow or tab keys or other standard exit
methods, the user is advised of the method for moving focus away.

Note

Since any content that does not meet this success criterion can interfere with a user's
ability to use the whole page, all content on the Web page (whether it is used to
meet other success criteria or not) must meet this success criterion. See Conformance Requirement 5: Non-Interference.

For each time limit that is set by the content, at least one of the following is true:

Turn off

The user is allowed to turn off the time limit before encountering it; or

Adjust

The user is allowed to adjust the time limit before encountering it over a wide range
that is at least ten times the length of the default setting; or

Extend

The user is warned before time expires and given at least 20 seconds to extend the
time limit with a simple action (for example, "press the space bar"), and the user
is allowed to extend the time limit at least ten times; or

Real-time Exception

The time limit is a required part of a real-time event (for example, an auction),
and no alternative to the time limit is possible; or

Essential Exception

The time limit is essential and extending it would invalidate the activity; or

20 Hour Exception

The time limit is longer than 20 hours.

Note

This success criterion helps ensure that users can complete tasks without unexpected
changes in content or context that are a result of a time limit. This success criterion
should be considered in conjunction with Success Criterion 3.2.1, which puts limits on changes of content or context as a result of user action.

For moving, blinking, scrolling, or auto-updating information, all of the following are true:

Moving, blinking, scrolling

For any moving, blinking or scrolling information that (1) starts automatically, (2)
lasts more than five seconds, and (3) is presented in parallel with other content,
there is a mechanism for the user to pause, stop, or hide it unless the movement, blinking, or scrolling is part of an activity
where it is essential; and

Auto-updating

For any auto-updating information that (1) starts automatically and (2) is presented
in parallel with other content, there is a mechanism for the user to pause, stop,
or hide it or to control the frequency of the update unless the auto-updating is part
of an activity where it is essential.

Note

For requirements related to flickering or flashing content, refer to Guideline 2.3.

Note

Since any content that does not meet this success criterion can interfere with a user's
ability to use the whole page, all content on the Web page (whether it is used to
meet other success criteria or not) must meet this success criterion. See Conformance Requirement 5: Non-Interference.

Note

Content that is updated periodically by software or that is streamed to the user agent
is not required to preserve or present information that is generated or received between
the initiation of the pause and resuming presentation, as this may not be technically
possible, and in many situations could be misleading to do so.

Note

An animation that occurs as part of a preload phase or similar situation can be considered
essential if interaction cannot occur during that phase for all users and if not indicating
progress could confuse users or cause them to think that content was frozen or broken.

Users are warned of the duration of any user inactivity that could cause data loss, unless the data is preserved for more than 20 hours when the user does not take any actions.

Note

Privacy regulations may require explicit user consent before user identification has been authenticated and before user data is preserved. In cases where the user is a minor, explicit consent may not be solicited in most jurisdictions, countries or regions. Consultation with privacy professionals and legal counsel is advised when considering data preservation as an approach to satisfy this success criterion.

Since any content that does not meet this success criterion can interfere with a user's
ability to use the whole page, all content on the Web page (whether it is used to
meet other success criteria or not) must meet this success criterion. See Conformance Requirement 5: Non-Interference.

Functionality that can be operated by device motion or user motion can also be operated by user interface components and responding to the motion can be disabled to prevent accidental actuation, except when:

Web content does not restrict use of input modalities available on a platform except where the restriction is essential, required to ensure the security of the content, or required to respect user settings.

The human language of each passage or phrase in the content can be programmatically determined except for proper names, technical terms, words of indeterminate language, and words
or phrases that have become part of the vernacular of the immediately surrounding
text.

When text requires reading ability more advanced than the lower secondary education level after removal of proper names and titles, supplemental content, or a version that does not require reading ability more advanced than the lower
secondary education level, is available.

For Web pages that cause legal commitments or financial transactions for the user to occur, that modify or delete user-controllable data in data storage systems, or that submit user test responses, at least one of
the following is true:

Reversible

Submissions are reversible.

Checked

Data entered by the user is checked for input errors and the user is provided an opportunity to correct them.

Confirmed

A mechanism is available for reviewing, confirming, and correcting information before finalizing the submission.

In content implemented using markup languages, elements have complete start and end
tags, elements are nested according to their specifications, elements do not contain
duplicate attributes, and any IDs are unique, except where the specifications allow
these features.

Note

Start and end tags that are missing a critical character in their formation, such
as a closing angle bracket or a mismatched attribute value quotation mark are not
complete.

This success criterion is primarily for Web authors who develop or script their own
user interface components. For example, standard HTML controls already meet this success
criterion when used according to specification.

This section lists requirements for conformance to WCAG 2.1. It also gives information about how to make conformance claims, which are optional. Finally, it describes what it means to be accessibility supported, since only accessibility-supported ways of using technologies can be relied upon for conformance. Understanding Conformance includes further explanation of the accessibility-supported concept.

The main content of WCAG 2.1 is normative and defines requirements that impact conformance claims. Introductory material, appendices, sections marked as "non-normative", diagrams, examples, and notes are informative (non-normative). Non-normative material provides advisory information to help interpret the guidelines but does not create requirements that impact a conformance claim.

The key words MAY, MUST, MUST NOT, NOT RECOMMENDED, RECOMMENDED, SHOULD, and SHOULD NOT are to be interpreted as described in [RFC2119].

For Level AA conformance, the Web page satisfies all the Level A and Level AA Success Criteria, or a Level AA conforming alternate version is provided.

For Level AAA conformance, the Web page satisfies all the Level A, Level AA and Level AAA Success Criteria, or a Level AAA conforming alternate version is provided.

Note

Although conformance can only be achieved at the stated levels, authors are encouraged to report (in their claim) any progress toward meeting success criteria from all levels beyond the achieved level of conformance.

Note

It is not recommended that Level AAA conformance be required as a general policy for entire sites because it is not possible to satisfy all Level AAA Success Criteria for some content.

Conformance (and conformance level) is for full Web page(s) only, and cannot be achieved if part of a Web page is excluded.

Note

For the purpose of determining conformance, alternatives to part of a page's content are considered part of the page when the alternatives can be obtained directly from the page, e.g., a long description or an alternative presentation of a video.

New A full page includes each variation of the page that is automatically presented by the page for various screen sizes (e.g. variations in a responsive Web page). Each of these variations needs to conform (or needs to have a conforming alternate version) in order for the entire page to conform.

When a Web page is one of a series of Web pages presenting a process (i.e., a sequence of steps that need to be completed in order to accomplish an activity), all Web pages in the process conform at the specified level or better. (Conformance is not possible at a particular level if any page in the process does not conform at that level or better.)

An online store has a series of pages that are used to select and purchase products. All pages in the series from start to finish (checkout) conform in order for any page that is part of the process to conform.

If technologies are used in a way that is not accessibility supported, or if they are used in a non-conforming way, then they do not block the ability of users to access the rest of the page. In addition, the Web page as a whole continues to meet the conformance requirements under each of the following conditions:

when any technology that is not relied upon is turned on in a user agent,

when any technology that is not relied upon is turned off in a user agent, and

when any technology that is not relied upon is not supported by a user agent

In addition, the following success criteria apply to all content on the page, including content that is not otherwise relied upon to meet conformance, because failure to meet them could interfere with any use of the page:

1.4.2 - Audio Control,

2.1.2 - No Keyboard Trap,

2.3.1 - Three Flashes or Below Threshold, and

2.2.2 - Pause, Stop, Hide.

Note

If a page cannot conform (for example, a conformance test page or an example page), it cannot be included in the scope of conformance or in a conformance claim.

Sometimes, Web pages are created that will later have additional content added to them. For example, an email program, a blog, an article that allows users to add comments, or applications supporting user-contributed content. Another example would be a page, such as a portal or news site, composed of content aggregated from multiple contributors, or sites that automatically insert content from other sources over time, such as when advertisements are inserted dynamically.

In these cases, it is not possible to know at the time of original posting what the uncontrolled content of the pages will be. It is important to note that the uncontrolled content can affect the accessibility of the controlled content as well. Two options are available:

A determination of conformance can be made based on best knowledge. If a page of this type is monitored and repaired (non-conforming content is removed or brought into conformance) within two business days, then a determination or claim of conformance can be made since, except for errors in externally contributed content which are corrected or removed when encountered, the page conforms. No conformance claim can be made if it is not possible to monitor or correct non-conforming content;

OR

A "statement of partial conformance" may be made that the page does not conform, but could conform if certain parts were removed. The form of that statement would be, "This page does not conform, but would conform to WCAG 2.1 at level X if the following parts from uncontrolled sources were removed." In addition, the following would also be true of uncontrolled content that is described in the statement of partial conformance:

It is not content that is under the author's control.

It is described in a way that users can identify (e.g., they cannot be described as "all parts that we do not control" unless they are clearly marked as such.)

A "statement of partial conformance due to language" may be made when the page does not conform, but would conform if accessibility support existed for (all of) the language(s) used on the page. The form of that statement would be, "This page does not conform, but would conform to WCAG 2.1 at level X if accessibility support existed for the following language(s):"

shortened form of a word, phrase, or name where the abbreviation has not become part
of the language

Note

This includes initialisms and acronyms where:

initialisms are shortened forms of a name or phrase made from the initial letters of words or
syllables contained in that name or phrase

Note

Not defined in all languages.

SNCF is a French initialism that contains the initial letters of the Société Nationale des Chemins de Fer, the French national railroad.

ESP is an initialism for extrasensory perception.

acronyms are abbreviated forms made from the initial letters or parts of other words (in a
name or phrase) which may be pronounced as a word

NOAA is an acronym made from the initial letters of the National Oceanic and Atmospheric
Administration in the United States.

Note

Some companies have adopted what used to be an initialism as their company name. In
these cases, the new name of the company is the letters (for example, Ecma) and the
word is no longer considered an abbreviation.

To qualify as an accessibility-supported use of a Web content technology (or feature
of a technology), both 1 and 2 must be satisfied for a Web content technology (or
feature):

The way that the Web content technology is used must be supported by users' assistive technology (AT). This means that the way that the technology is used has been tested for interoperability
with users' assistive technology in the human language(s) of the content,

AND

The Web content technology must have accessibility-supported user agents that are
available to users. This means that at least one of the following four statements is true:

The technology is supported natively in widely-distributed user agents that are also
accessibility supported (such as HTML and CSS);

OR

The technology is supported in a widely-distributed plug-in that is also accessibility
supported;

OR

The content is available in a closed environment, such as a university or corporate
network, where the user agent required by the technology and used by the organization
is also accessibility supported;

OR

The user agent(s) that support the technology are accessibility supported and are
available for download or purchase in a way that:

does not cost a person with a disability any more than a person without a disability
and

is as easy to find and obtain for a person with a disability as it is for a person
without disabilities.

When a Web Technology is used in a way that is "accessibility supported," it does not imply that the entire
technology or all uses of the technology are supported. Most technologies, including
HTML, lack support for at least one feature or use. Pages conform to WCAG only if
the uses of the technology that are accessibility supported can be relied upon to
meet WCAG requirements.

Note

When citing Web content technologies that have multiple versions, the version(s) supported
should be specified.

Note

One way for authors to locate uses of a technology that are accessibility supported
would be to consult compilations of uses that are documented to be accessibility supported.
(See Understanding Accessibility-Supported Web Technology Uses.) Authors, companies, technology vendors, or others may document accessibility-supported
ways of using Web content technologies. However, all ways of using technologies in
the documentation would need to meet the definition of accessibility-supported Web
content technologies above.

alternative for time-based media

document including correctly sequenced text descriptions of time-based visual and
auditory information and providing a means for achieving the outcomes of any time-based
interaction

Note

A screenplay used to create the synchronized media content would meet this definition
only if it was corrected to accurately represent the final synchronized media after
editing.

ambiguous to users in general

the purpose cannot be determined from the link and all information of the Web page
presented to the user simultaneously with the link (i.e., readers without disabilities
would not know what a link would do until they activated it)

The word guava in the following sentence "One of the notable exports is guava" is
a link. The link could lead to a definition of guava, a chart listing the quantity
of guava exported or a photograph of people harvesting guava. Until the link is activated,
all readers are unsure and the person with a disability is not at any disadvantage.

ASCII art

picture created by a spatial arrangement of characters or glyphs (typically from the
95 printable characters defined by ASCII)

assistive technology (as used in this document)

hardware and/or software that acts as a user agent, or along with a mainstream user agent, to provide functionality to meet the requirements
of users with disabilities that go beyond those offered by mainstream user agents

Assistive technologies often communicate data and messages with mainstream user agents
by using and monitoring APIs.

Note

The distinction between mainstream user agents and assistive technologies is not absolute.
Many mainstream user agents provide some features to assist individuals with disabilities.
The basic difference is that mainstream user agents target broad and diverse audiences
that usually include people with and without disabilities. Assistive technologies
target narrowly defined populations of users with specific disabilities. The assistance
provided by an assistive technology is more specific and appropriate to the needs
of its target users. The mainstream user agent may provide important functionality
to assistive technologies like retrieving Web content from program objects or parsing
markup into identifiable bundles.

Assistive technologies that are important in the context of this document include
the following:

screen magnifiers, and other visual reading assistants, which are used by people with
visual, perceptual and physical print disabilities to change text font, size, spacing,
color, synchronization with speech, etc. in order to improve the visual readability
of rendered text and images;

screen readers, which are used by people who are blind to read textual information
through synthesized speech or braille;

text-to-speech software, which is used by some people with cognitive, language, and
learning disabilities to convert text into synthetic speech;

speech recognition software, which may be used by people who have some physical disabilities;

alternative keyboards, which are used by people with certain physical disabilities
to simulate the keyboard (including alternate keyboards that use head pointers, single
switches, sip/puff and other special input devices.);

alternative pointing devices, which are used by people with certain physical disabilities
to simulate mouse pointing and button activations.

audio

the technology of sound reproduction

Note

Audio can be created synthetically (including speech synthesis), recorded from real
world sounds, or both.

audio description

narration added to the soundtrack to describe important visual details that cannot
be understood from the main soundtrack alone

Where all of the video information is already provided in existing audio, no additional audio description is necessary.

Note

Also called "video description" and "descriptive narration."

audio-only

a time-based presentation that contains only audio (no video and no interaction)

blinking

switch back and forth between two visual states in a way that is meant to draw attention

Note

See also flash. It is possible for something to be large enough and blink brightly enough at the
right frequency to be also classified as a flash.

blocks of text

more than one sentence of text

CAPTCHA

initialism for "Completely Automated Public Turing test to tell Computers and Humans
Apart"

Note

CAPTCHA tests often involve asking the user to type in text that is displayed in an
obscured image or audio file.

Note

A Turing test is any system of tests designed to differentiate a human from a computer.
It is named after famed computer scientist Alan Turing. The term was coined by researchers
at Carnegie Mellon University.

Captions are similar to dialogue-only subtitles except captions convey not only the
content of spoken dialogue, but also equivalents for non-dialogue audio information
needed to understand the program content, including sound effects, music, laughter,
speaker identification and location.

Note

Closed Captions are equivalents that can be turned on and off with some players.

Note

Open Captions are any captions that cannot be turned off. For example, if the captions
are visual equivalent images of text embedded in video.

Note

Captions should not obscure or obstruct relevant information in the video.

Note

In some countries, captions are called subtitles.

Note

Audio descriptions can be, but do not need to be, captioned since they are descriptions of information
that is already presented visually.

changes of context

major changes in the content of the Web page that, if made without user awareness, can disorient users who are not able to view
the entire page simultaneously

A change of content is not always a change of context. Changes in content, such as
an expanding outline, dynamic menu, or a tab control do not necessarily change the
context, unless they also change one of the above (e.g., focus).

Opening a new window, moving focus to a different component, going to a new page (including
anything that would look to a user as if they had moved to a new page) or significantly
re-arranging the content of a page are examples of changes of context.

conformance

satisfying all the requirements of a given standard, guideline or specification

the non-conforming version can only be reached from the conforming version, or

the non-conforming version can only be reached from a conforming page that also provides
a mechanism to reach the conforming version

Note

In this definition, "can only be reached" means that there is some mechanism, such
as a conditional redirect, that prevents a user from "reaching" (loading) the non-conforming
page unless the user had just come from the conforming version.

Note

The alternate version does not need to be matched page for page with the original
(e.g., the conforming alternate version may consist of multiple pages).

Note

If multiple language versions are available, then conforming alternate versions are
required for each language offered.

Note

Alternate versions may be provided to accommodate different technology environments
or user groups. Each version should be as conformant as possible. One version would
need to be fully conformant in order to meet conformance requirement 1.

Note

The conforming alternative version does not need to reside within the scope of conformance,
or even on the same Web site, as long as it is as freely available as the non-conforming
version.

Note

Alternate versions should not be confused with supplementary content, which support the original page and enhance comprehension.

Note

Setting user preferences within the content to produce a conforming version is an
acceptable mechanism for reaching another version as long as the method used to set
the preferences is accessibility supported.

Contrast ratios can range from 1 to 21 (commonly written 1:1 to 21:1).

Note

Because authors do not have control over user settings as to how text is rendered
(for example font smoothing or anti-aliasing), the contrast ratio for text can be
evaluated with anti-aliasing turned off.

Note

For the purpose of Success Criteria 1.4.3 and 1.4.6, contrast is measured with respect
to the specified background over which the text is rendered in normal usage. If no
background color is specified, then white is assumed.

Note

Background color is the specified color of content over which the text is to be rendered
in normal usage. It is a failure if no background color is specified when the text
color is specified, because the user's default background color is unknown and cannot
be evaluated for sufficient contrast. For the same reason, it is a failure if no text
color is specified when a background color is specified.

Note

When there is a border around the letter, the border can add contrast and would be
used in calculating the contrast between the letter and its background. A narrow border
around the letter would be used as the letter. A wide border around the letter that
fills in the inner details of the letters acts as a halo and would be considered background.

Note

WCAG conformance should be evaluated for color pairs specified in the content that
an author would expect to appear adjacent in typical presentation. Authors need not
consider unusual presentations, such as color changes made by the user agent, except
where caused by authors' code.

correct reading sequence

any sequence where words and paragraphs are presented in an order that does not change
the meaning of the content

CSS pixel

visual angle of about 0.0213 degrees

A CSS pixel is the canonical unit of measure for all lengths and measurements in CSS.
This unit is density-independent, and distinct from actual hardware pixels present
in a display. User agents and operating systems should ensure that a CSS pixel is
set as closely as possible to the CSS Values and Units Module Level 3 reference pixel [css3-values], which takes into account the physical dimensions of the display
and the assumed viewing distance (factors that cannot be determined by content authors).

down-event

platform event that occurs when the trigger stimulus of a pointer is depressed

The down-event may have different names on different platforms, such as "touchstart" or "mousedown".

emergency

a sudden, unexpected situation or occurrence that requires immediate action to preserve
health, safety, or property

essential

if removed, would fundamentally change the information or functionality of the content,
and information and functionality cannot be achieved in another way that would conform

extended audio description

audio description that is added to an audiovisual presentation by pausing the video so that there is time to add additional description

Note

This technique is only used when the sense of the video would be lost without the additional audio description and the pauses between dialogue/narration are too short.

flash

a pair of opposing changes in relative luminance that can cause seizures in some people if it is large enough and in the right frequency
range

a flash or rapidly changing image sequence is below the threshold (i.e., content passes) if any of the following are true:

there are no more than three general flashes and / or no more than three red flashes within any one-second period; or

the combined area of flashes occurring concurrently occupies no more than a total
of .006 steradians within any 10 degree visual field on the screen (25% of any 10
degree visual field on the screen) at typical viewing distance

where:

A general flash is defined as a pair of opposing changes in relative luminance of 10% or more of the maximum relative luminance where the relative luminance of
the darker image is below 0.80; and where "a pair of opposing changes" is an increase
followed by a decrease, or a decrease followed by an increase, and

A red flash is defined as any pair of opposing transitions involving a saturated red

Exception: Flashing that is a fine, balanced, pattern such as white noise or an alternating
checkerboard pattern with "squares" smaller than 0.1 degree (of visual field at typical
viewing distance) on a side does not violate the thresholds.

Note

For general software or Web content, using a 341 x 256 pixel rectangle anywhere on
the displayed screen area when the content is viewed at 1024 x 768 pixels will provide
a good estimate of a 10 degree visual field for standard screen sizes and viewing
distances (e.g., 15-17 inch screen at 22-26 inches). (Higher resolutions displays
showing the same rendering of the content yield smaller and safer images so it is
lower resolutions that are used to define the thresholds.)

Note

A transition is the change in relative luminance (or relative luminance/color for
red flashing) between adjacent peaks and valleys in a plot of relative luminance (or
relative luminance/color for red flashing) measurement against time. A flash consists
of two opposing transitions.

Note

The current working definition in the field for "pair of opposing transitions involving a saturated red" is where, for either or both states involved in each transition, R/(R+ G + B) >=
0.8, and the change in the value of (R-G-B)x320 is > 20 (negative values of (R-G-B)x320
are set to zero) for both transitions. R, G, B values range from 0-1 as specified
in “relative luminance” definition. [HARDING-BINNIE]

Note

Tools are available that will carry out analysis from video screen capture. However,
no tool is necessary to evaluate for this condition if flashing is less than or equal
to 3 flashes in any one second. Content automatically passes (see #1 and #2 above).

human language

language that is spoken, written or signed (through visual or tactile means) to communicate
with humans

Information that is provided by the user but that falls outside the required data
format or values

jargon

words used in a particular way by people in a particular field

The word StickyKeys is jargon from the field of assistive technology/accessibility.

keyboard interface

interface used by software to obtain keystroke input

Note

A keyboard interface allows users to provide keystroke input to programs even if the
native technology does not contain a keyboard.

Note

A touchscreen PDA has a keyboard interface built into its operating system as well
as a connector for external keyboards. Applications on the PDA can use the interface
to obtain keyboard input either from an external keyboard or from other applications
that provide simulated keyboard output, such as handwriting interpreters or speech-to-text
applications with "keyboard emulation" functionality.

Note

Operation of the application (or parts of the application) through a keyboard-operated
mouse emulator, such as MouseKeys, does not qualify as operation through a keyboard
interface because operation of the program is through its pointing device interface,
not through its keyboard interface.

keyboard shortcut

alternative means of triggering an action by the pressing of one or more keys

A label is presented to all users whereas the name may be hidden and only exposed by assistive technology. In many (but not all) cases
the name and the label are the same.

Note

The term label is not limited to the label element in HTML.

large scale (text)

with at least 18 point or 14 point bold or font size that would yield equivalent size
for Chinese, Japanese and Korean (CJK) fonts

Note

Fonts with extraordinarily thin strokes or unusual features and characteristics that
reduce the familiarity of their letter forms are harder to read, especially at lower
contrast levels.

Note

Font size is the size when the content is delivered. It does not include resizing
that may be done by a user.

Note

The actual size of the character that a user sees is dependent both on the author-defined
size and the user's display or user-agent settings. For many mainstream body text
fonts, 14 and 18 point is roughly equivalent to 1.2 and 1.5 em or to 120% or 150%
of the default size for body text (assuming that the body font is 100%), but authors
would need to check this for the particular fonts in use. When fonts are defined in
relative units, the actual point size is calculated by the user agent for display.
The point size should be obtained from the user agent, or calculated based on font
metrics as the user agent does, when evaluating this success criterion. Users who
have low vision would be responsible for choosing appropriate settings.

Note

When using text without specifying the font size, the smallest font size used on major
browsers for unspecified text would be a reasonable size to assume for the font. If
a level 1 heading is rendered in 14pt bold or higher on major browsers, then it would
be reasonable to assume it is large text. Relative scaling can be calculated from
the default sizes in a similar fashion.

Note

The 18 and 14 point sizes for roman texts are taken from the minimum size for large
print (14pt) and the larger standard font size (18pt). For other fonts such as CJK
languages, the "equivalent" sizes would be the minimum large print size used for those
languages and the next larger standard large print size.

legal commitments

transactions where the person incurs a legally binding obligation or benefit

A marriage license, a stock trade (financial and legal), a will, a loan, adoption,
signing up for the army, a contract of any type, etc.

link purpose

nature of the result obtained by activating a hyperlink

live

information captured from a real-world event and transmitted to the receiver with
no more than a broadcast delay

Note

A broadcast delay is a short (usually automated) delay, for example used in order
to give the broadcaster time to cue or censor the audio (or video) feed, but not sufficient
to allow significant editing.

Note

If information is completely computer generated, it is not live.

lower secondary education level

the two or three year period of education that begins after completion of six years
of school and ends nine years after the beginning of primary education

Note

This definition is based on the International Standard Classification of Education
[UNESCO].

The mechanism needs to meet all success criteria for the conformance level claimed.

media alternative for text

media that presents no more information than is already presented in text (directly
or via text alternatives)

Note

A media alternative for text is provided for those who benefit from alternate representations
of text. Media alternatives for text may be audio-only, video-only (including sign-language
video), or audio-video.

motion animation

addition of steps between conditions to create the illusion of movement or to give a sense of a smooth transition

For example, an element which moves into place or changes size while appearing is considered to be animated. An element which appears instantly without transitioning is not using animation. Motion animation does not include changes of color, blurring or opacity.

name

text by which software can identify a component within Web content to the user

Note

The name may be hidden and only exposed by assistive technology, whereas a label is presented to all users. In many (but not all) cases, the label and the name are
the same.

Note

This is unrelated to the name attribute in HTML.

navigated sequentially

navigated in the order defined for advancing focus (from one element to the next)
using a keyboard interface

on the most common sized desktop/laptop display with the viewport maximized

Note

Since people generally keep their computers for several years, it is best not to rely
on the latest desktop/laptop display resolutions but to consider the common desktop/laptop
display resolutions over the course of several years when making this evaluation.

paused

stopped by user request and not resumed until requested by user

pointer input

input device that can target a specific coordinate (or set of coordinates) on a screen,
such as a mouse, pen, or touch contact

six year time period that begins between the ages of five and seven, possibly without
any previous education

Note

This definition is based on the International Standard Classification of Education
[UNESCO].

process

series of user actions where each action is required in order to complete an activity

Successful use of a series of Web pages on a shopping site requires users to view
alternative products, prices and offers, select products, submit an order, provide
shipping information and provide payment information.

An account registration page requires successful completion of a Turing test before
the registration form can be accessed.

programmatically determined (programmatically determinable)

determined by software from author-supplied data provided in a way that different
user agents, including assistive technologies, can extract and present this information to users in different modalities

Note

Determined in a markup language from elements and attributes that are accessed directly
by commonly available assistive technology.

Note

Determined from technology-specific data structures in a non-markup language and exposed
to assistive technology via an accessibility API that is supported by commonly available
assistive technology.

In HTML, information that is programmatically determinable from a link in English
includes text that is in the same paragraph, list, or table cell as the link or in
a table header cell that is associated with the table cell that contains the link.

Note

Since screen readers interpret punctuation, they can also provide the context from
the current sentence, when the focus is on a link in that sentence.

programmatically set

set by software using methods that are supported by user agents, including assistive
technologies

pure decoration

serving only an aesthetic purpose, providing no information, and having no functionality

Note

Text is only purely decorative if the words can be rearranged or substituted without
changing their purpose.

The cover page of a dictionary has random words in very light text in the background.

real-time event

event that a) occurs at the same time as the viewing and b) is not completely generated
by the content

A Webcast of a live performance (occurs at the same time as the viewing and is not
prerecorded).

An on-line auction with people bidding (occurs at the same time as the viewing).

Live humans interacting in a virtual world using avatars (is not completely generated
by the content and occurs at the same time as the viewing).

region

perceivable, programmatically determined section of content

Note

In HTML, any area designated with a landmark role would be a region.

relationships

meaningful associations between distinct pieces of content

relative luminance

the relative brightness of any point in a colorspace, normalized to 0 for darkest
black and 1 for lightest white

The "^" character is the exponentiation operator. (Formula taken from [sRGB] and
[IEC-4WD]).

Note

Almost all systems used today to view Web content assume sRGB encoding. Unless it
is known that another color space will be used to process and display the content,
authors should evaluate using sRGB colorspace. If using other color spaces, see Understanding Success Criterion 1.4.3.

Note

If dithering occurs after delivery, then the source color value is used. For colors
that are dithered at the source, the average values of the colors that are dithered
should be used (average R, average G, and average B).

Note

Tools are available that automatically do the calculations when testing contrast and
flash.

text or number by which software can identify the function of a component within Web
content

A number that indicates whether an image functions as a hyperlink, command button,
or check box.

same functionality

same result when used

A submit "search" button on one Web page and a "find" button on another Web page may
both have a field to enter a term and list topics in the Web site related to the term
submitted. In this case, they would have the same functionality but would not be labeled
consistently.

same relative order

same position relative to other items

Note

Items are considered to be in the same relative order even if other items are inserted
or removed from the original order. For example, expanding navigation menus may insert
an additional level of detail or a secondary navigation section may be inserted into
the reading order.

satisfies a success criterion

the success criterion does not evaluate to 'false' when applied to the page

section

a self-contained portion of written content that deals with one or more related topics
or thoughts

Note

A section may consist of one or more paragraphs and include graphics, tables, lists
and sub-sections.

set of web pages

collection of web pages that share a common purpose and that are created by the same author, group or organization

Examples include a publication which is split across multiple Web pages, where each page contains
one chapter or other significant section of the work. The publication is logically
a single contiguous unit, and contains navigation features that enable access to the
full set of pages.

Note

Different language versions would be considered different sets of Web pages.

sign language

a language using combinations of movements of the hands and arms, facial expressions,
or body positions to convey meaning

sign language interpretation

translation of one language, generally a spoken language, into a sign language

Note

True sign languages are independent languages that are unrelated to the spoken language(s)
of the same country or region.

single pointer

pointer input that operates with one point of contact with the screen, including single taps and clicks, double-taps and clicks, long presses, and path-based gestures

specific sensory experience

a sensory experience that is not purely decorative and does not primarily convey important
information or perform a function

Examples include a performance of a flute solo, works of visual art etc.

state

dynamic property expressing characteristics of a user interface component that may change in response to user action or automated processes

States do not affect the nature of the component, but represent data associated with the component or user interaction possibilities. Examples include focus, hover, select, press, check, visited/unvisited, and expand/collapse.

status message

change in content that is not a change of context, and that provides information to the user on the success or results of an action, on the waiting state of an application, on the progress of a process, or on the existence of errors

structure

The way the parts of a Web page are organized in relation to each other; and

A paragraph summarizing the major outcomes and recommendations made in a research
study.

synchronized media

audio or video synchronized with another format for presenting information and/or with time-based
interactive components, unless the media is a media alternative for text that is clearly labeled as such

target

region of the display that will accept a pointer action, such as the interactive area of a user interface component

Note

If two or more touch targets are overlapping, the overlapping area should not be included in the measurement of the target size, except when the overlapping targets perform the same action or open the same page.

As used in these guidelines "Web Technology" and the word "technology" (when used
alone) both refer to Web Content Technologies.

Note

Web content technologies may include markup languages, data formats, or programming
languages that authors may use alone or in combination to create end-user experiences
that range from static Web pages to synchronized media presentations to dynamic Web
applications.

Note

Some common examples of Web content technologies include HTML, CSS, SVG, PNG, PDF,
Flash, and JavaScript.

Text that is programmatically associated with non-text content or referred to from text that is programmatically associated with non-text content.
Programmatically associated text is text whose location can be programmatically determined
from the non-text content.

An image of a chart is described in text in the paragraph after the chart. The short
text alternative for the chart indicates that a description follows.

platform event that occurs when the trigger stimulus of a pointer is released

The up-event may have different names on different platforms, such as "touchend" or "mouseup".

used in an unusual or restricted way

words used in such a way that requires users to know exactly which definition to apply
in order to understand the content correctly

The term "gig" means something different if it occurs in a discussion of music concerts
than it does in article about computer hard drive space, but the appropriate definition
can be determined from context. By contrast, the word "text" is used in a very specific
way in WCAG 2.1, so a definition is supplied in the glossary.

user agent

any software that retrieves and presents Web content for users

Web browsers, media players, plug-ins, and other programs — including assistive technologies — that help in retrieving, rendering, and interacting with Web content.

user-controllable

data that is intended to be accessed by users

Note

This does not refer to such things as Internet logs and search engine monitoring data.

Name and address fields for a user's account.

user interface component

a part of the content that is perceived by users as a single control for a distinct
function

Note

Multiple user interface components may be implemented as a single programmatic element.
Components here is not tied to programming techniques, but rather to what the user
perceives as separate controls.

Note

User interface components include form elements and links as well as components generated
by scripts.

Note

What is meant by "component" or "user interface component" here is also sometimes
called "user interface element".

An applet has a "control" that can be used to move through content by line or page
or random access. Since each of these would need to have a name and be settable independently,
they would each be a "user interface component."

user inactivity

any continuous period of time where no user actions occur

The method of tracking will be determined by the web site or application.

video

the technology of moving or sequenced pictures or images

Note

Video can be made up of animated or photographic images, or both.

video-only

a time-based presentation that contains only video (no audio and no interaction)

viewport

object in which the user agent presents content

Note

The user agent presents content through one or more viewports. Viewports include windows, frames,
loudspeakers, and virtual magnifying glasses. A viewport may contain another viewport
(e.g., nested frames). Interface components created by the user agent such as prompts,
menus, and alerts are not viewports.

a non-embedded resource obtained from a single URI using HTTP plus any other resources
that are used in the rendering or intended to be rendered together with it by a user agent

Note

Although any "other resources" would be rendered together with the primary resource,
they would not necessarily be rendered simultaneously with each other.

Note

For the purposes of conformance with these guidelines, a resource must be "non-embedded"
within the scope of conformance to be considered a Web page.

A Web resource including all embedded images and media.

A Web mail program built using Asynchronous JavaScript and XML (AJAX). The program
lives entirely at http://example.com/mail, but includes an inbox, a contacts area
and a calendar. Links or buttons are provided that cause the inbox, contacts, or calendar
to display, but do not change the URI of the page as a whole.

A customizable portal site, where users can choose content to display from a set of
different content modules.

When you enter "http://shopping.example.com/" in your browser, you enter a movie-like
interactive shopping environment where you visually move around in a store dragging
products off of the shelves around you and into a visual shopping cart in front of
you. Clicking on a product causes it to be demonstrated with a specification sheet
floating alongside. This might be a single-page Web site or just one page within a
Web site.

This section contains a listing of common user interface component input purposes. The terms below are not keywords that must be used, but instead represent purposes that must be captured in the taxonomy adopted by a webpage. Where applicable, authors mark up controls with the chosen taxonomy to indicate the semantic purpose. This provides the potential for user agents and assistive technologies to apply personalized presentations that can enable more people to understand and use the content.

Note

The list of input type purposes is based on the control purposes defined in the HTML 5.2 Autofill field section, but it is important to understand that a different technology may have some or all of the same concepts defined in its specification and only the concepts that are mapped to the meanings below are required.

The following input control purposes are intended to relate to the user of the content and pertain only to information related to that individual.

new-password - A new password (e.g., when creating an account or changing a password)

current-password - The current password for the account identified by the username field (e.g., when logging in)

organization - Company name corresponding to the person, address, or contact information in the other fields associated with this field

street-address - Street address (multiple lines, newlines preserved)

address-line1 - Street address (one line per field, line 1)

address-line2 - Street address (one line per field, line 2)

address-line3 - Street address (one line per field, line 3)

address-level4 - The most fine-grained administrative level, in addresses with four administrative levels

address-level3 - The third administrative level, in addresses with three or more administrative levels

address-level2 - The second administrative level, in addresses with two or more administrative levels; in the countries with two administrative levels, this would typically be the city, town, village, or other locality within which the relevant street address is found

address-level1 - The broadest administrative level in the address, i.e., the province within which the locality is found; for example, in the US, this would be the state; in Switzerland it would be the canton; in the UK, the post town

2017-03-16: Remove Success Criteria that were listed as "proposals" in the First Public Working Draft but not yet past the Working Group consensus process.

2017-04-13: Added definition of easily available (since removed).

2017-04-14: Accepted new version of Accidental Activation (since renamed Pointer Cancellation), changing "Timing of event is essential..." to "Down-event activation event is essential..." and removing note about applicability when AT that remaps touch gestures is not turned on.

2017-12-05: Reworded Timeouts with definition for user inactivity and changed maximum time limit. Renamed Purpose of Controls to Identify Common Purpose (later renamed Identify Input Purpose) and restructured to remove definitions for conventional buttons or controls, fields and links, and instead reference a new section Common Control Purposes (since removed). Restructured Content on Hover or Focus. Changed Device Sensors to Motion Actuation, restructured, and removed term for device sensor. Changed Accidental Activation to Pointer Cancellation, restructured, added term for down-event and single pointer, and removed term for single pointer activation. Changed Change of Content to Status Messages, simplified wording, added term for status messages,
and removed terms for change of content and primary purpose of the page.

This publication has been funded in part with U.S. Federal funds from the Health and Human Services, National Institute on Disability, Independent Living, and Rehabilitation Research (NIDILRR), initially under contract number ED-OSE-10-C-0067 and now under contract number HHSP23301500054C. The content of this publication does not necessarily reflect the views or policies of the U.S. Department of Health and Human Services or the U.S. Department of Education, nor does mention of trade names, commercial products, or organizations imply endorsement by the U.S. Government.